Aerial ladder.



No. 677,282. Patented June 25, I901.

"F. S. SEAGRAVE.

AERIAL LADDER.

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AERIAL LADDER.

(Application filed Jan. 18, 1901. (In Model.)

Pa tented June 25, l90l.

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UNrTEn STATES ATENT FFICE.

FREDERIO S. SEAGRAVE, OF COLUMBUS, OHIO.

AERIAL LADDER.

SEEQIFIGAEIGN forming part of Letters Patent No. 677,282, dated June 25,1901.

Application filed January 18, 1901. Serial No. 43,702. (No model.)

To all whom it may concern.-

Be it known that I, FREDERIO S. SEAGRAVE, a citizen of the UnitedStates, residing at O0- lumbus, in the county of Franklin and State ofOhio, have invented a certain new and useful Improvementin AerialLadders, of which the following is a specification.

My invention relates to the improvement of aerial ladders, and hasparticular relation to mechanism for elevating the same from theturn-table of a ladder-truck.

The objects of myinvention are to provide improved mechanism forimparting an up ward swinging or elevating movement to a ladder and toprovide in conjunction therewith improved means for assisting in theele-,

vating operation and to produce certain improvements in details ofconstruction, which will be more fully pointed out hereinafter. Theseobjects I accomplish in the manner illustrated in the accompanyingdrawings, in which- Figure 1 is a side elevation of anaerialladder-truck turn-table, showing the rear portion of a laddermovably mounted thereon and showing my improved mechanism for op eratingthe same. Fig. 2 is a rear end elevation of the same. Fig. 3 is avertical section on line w :c of Fig. 1. Fig. 4 is a sectional view online y y of Fig. 1, the parts in rear of the rear frame-yoke beingomitted for the sake of clearness. Fig. 5 is a plan view of the rearportions of spring-carrying rods, which I employ in the mannerhereinafter described; and Fig. 6 is an enlarged sectional detail on theline 6 6 of Fig. 1.

Similar numerals refer to similar parts throughout the several views.

1 represents the parallel sills of a suitable form of aerial-laddertruck, and 2 the usual turn-table, which is mounted thereon. J ournaledon the turntable 2 is a transverse shaft 3, from opposite sides of thecenter of which rise ladder-supporting bars 4, the upper end of each ofwhich is rigidly connected with the rear end of one of the legs 5 of anaerial ladder.

6 represents upper and forwardly-inclined bars, which extend from theshaft 3 to points below the ladderdegs 5 and in front of the bars 4. Atthese points the bars 6 are extended upward and secured, as indicated at7, to the inner sides of the ladder-legs 5.

table, as shown.

The vertical end portions 6 of the forwardlyinclined bars 6 have pivotedtherein the ends of a transverseframe-bar 8, the latter having itscentral portion, as indicated more clearly in Fig. 3, enlarged andprovided with a central opening 9, between the upper and lower sides ofwhich is pivoted vertically a short bar 10, this bar 10 being in thenature of a boxing-piece, which is provided on its forward and rearsideswith outwardly-projecting internally-threaded boxing extensions orhubslO, which form extensions of an internally-threaded central openingin said bar 10. Rising from the turn-table 2 is a vertical yoke-frame11, and with the upper portion of the sides of this yoke-frame areconnected the rear portions of forwardly and downwardly extendingbrace-bars 12, the forward ends of which are secured to the turn- Thebars 12 are provided with rearward extensions, between which isjournaled the laterally-extending trunnions 13 of a boxing 14. lVithinthis boxing 14 there is a sleeve or boxing 14*,which is mounted formovement relatively to the outer boxing 14 by means of the pivot pointsor bearings 14', as seen best in Fig. 6, which pass through the boxing14 and into sockets in the sleeve 14, so that the parts constitute auniversal boxing or hearing. Through this sleeve 14 within the boxing 14extends the nnthreaded rear portion of a normally horizontaloperating-screw 15, on the outer or rear end of which is mounted a'large hand or balance wheel 16. The screw 15, which extends forwardlybeneath the rear portion of the ladder, passes through and engages thethreads of the hubs 10 of the pivoted bar 10.

Depending from the inner sides of the lad der-legs 5 are parallel barsor arms 17, the downwardly-extending portions of the latter extending inrear of the cross-bar 8. In the lower end portions of these arms 17 ispivoted a cross-piece 18, and through openings formed in saidcross-piece extend loosely the forward portions of parallel rods 19, therear end portions of these rods being pivotally connected at 20 with theside standards of the yokeframe 11. In front of the arms 17 each of therods 19 is surrounded by a coiled spring 21, the outer or forward end ofthis spring abutting against a transverse cross-bar 22, which con nectsthe forward ends of' said rods. The springs 21 are when the parts are inthe position indicated in the drawingsthat is,with the ladder in itslowered or normal position under compression.

In order to raise or swing the ladder upward, it is obvious that theoperation will consist in rotating the hand or balance wheel 16, causingthe boxing-hubs 10 to move rearwardly on said screw and resulting in aconsequent upward swinging movement of the ladder on its pivot orsupporting-shaft 3. In this operation it will be observed that thepressure exerted by the springs 21 upon the cross-piece 18 will assistin imparting the rearward movement to the rear portion of theladder-body, thus contributing aid in the operation of the screw.

It will be observed that owing to the fact that the cross-bar S ispivotally connected with the frame-bars 6 said cross-bar is permitted toassume such angles as the raising of the ladder must occasion, while thepivotal support ofthe screw bearing-piece 10 will permit of anydesirable lateral swinging motion of the ladder.

Importance is attached to the fact that the pivot 3 of the ladder isdisposed near the movable portion of the turn-table, that the screw ison a higher plane, and that the universal bearings of the said screw areupon opposite sides of this pivot, as is clearly shown in Fig. 1, as bythis construction I secure an ever increasing leverage as the ladder israised, and it will be readily seen that when the ladder has been raisedto an angle of, say, sixty or seventy degrees the greater portion of itsweight has been thrown beyond a vertical line through its pivotal point,and from this point on the ladder "ill move to its vertical positionwithout the aid of the screw, being thus aided by its own weight.

, By means of the universal joints or bearings at or near the oppositeends of the screw I provide against stripping of the threads of thescrew or other injury thereto, as is liable to occur where the screw isnot thus supported on uneven surfaces, which causes the ladder to swaysidewise, and consequently throw the parts out of alinement.

Having now fully described my invention, what I claim, and desire tosecure by Letters Patent, is-

1. In an aerial ladder, a ladder having its pivot located at a point inproximity to its turn-table, combined with an operating-screw disposedabove its pivot, and universal bearings for said screw upon oppositesides of said pivot, as set forth.

2. In an aerial-ladder-elevating mechanism, the combination with a truckand a ladder having its rear portion hinged thereon,

of a pivoted transverse bar 8 supported from the ladder, arms 1'7depending from said ladder, an operating-screw having a threadedconnection with said bar 8 and provided with an operating hand-wheel,rods 19 having a pivotal support at their rear ends and having theirouter portions supported by the arms 17 and springs 21 interposedbetween said arms 17 and enlargements at the ends of the rods 19,substantially as specified.

3. In an aerial ladder, a ladder having a low-down pivot, combined withan operatingscrew disposed above said pivot in universal bearingsdisposed upon opposite sides of said pivot, and a spring for assistingin raising the ladder, as set forth.

4. In an aerial ladder, aladder mounted on a low-down pivot, combinedwith an operating-screw mounted in universal bearings, disposed uponopposite sides of said pivot, a balance-wheel on one end of the screw,and a spring acting upon the ladder upon the op posite side of thepivot, as set forth.

5. In an aerial-ladder-elevating mechanism, the combination with atruclobody and a ladder having its rear portion hinged in connectionwith said truck, of a pivoted transverse bar supported from the ladder,a vertical pivoted bar in said transverse bar, a screw passing throughand engaging threads in the opening in the vertical bar, a universalboxing for the rear portion of said screw, and a hand or balance wheelon the screw beyond said universal boxing, as set forth.

6. In an aerial ladder, a bearing for the rear end of the screw, thesame consisting of a boxing mounted on horizontal pivots, and a sleevemounted within said boxingan-d upon vertical pivots, and adapted toreceive a screw, as set forth.

7. In an aerial ladder, a bearing. for the rear end of the screw, thesame comprisinga ring mounted at diametrically opposite points onhorizontal pivots, and a sleeve within said ring and mounted upondiametrically opposite pivots, at right angles to and traversing theplane of the first-mentioned pivots and adapted to receive theunthreaded portion of the screw, as set forth.

8. The combination with a screw, of a bearing therefor, consisting of aringmounted for to-and-fro movement upon diametrically opposite pivots,and a sleeve concentric with said ring and within the same, and pivotsfor the said sleeve disposed in planes at right angles to those of thering and adapted to receive the nnthreaded portion of the screw, as setforth.

FREDERIO S. SEAGRAVE.

In presence of A. L. PHELPS, \V. L. MoRRovv.

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